This is BS!Blizzard must have nothing but incompetent idiots for programmers as this is sloppy coding nothing more. they will blame the END USER for this as they always do I'm sure.Back in May they did a major patch and 1000's of users couldn't get the game running again and the wonderous Blizzard Tech support tried to blame the users, when in fact they FAILED to let anyone know that Windows update SP3 was at that time REQUIRED in order to play since the programmers decided to get even lazier with coding. Nice one Blizzard, you're slowly losing players and going to wonder why you cannot keep newer ones with issues the normal everyday computer illiterate person can't fix on their own.You people in Tech support NEED to understand that most computer users can only turn on their systems and click "Play" on ANY game and do not know what "Defrag" is much less how to delete a supposedly corrupt file that was fine for countless users only hours beforehand, much less even find the forums to ask how to fix the issue. Save yourself some time and money in the long run and hire REAL Beta testers to work out these bugs BEFORE going live with the latest patch that just pisses off loyal subscribers who only want to spend an hour in game rather than posting major complaints!Having Alpha & Beta tested many games over 2 decades, I can tell you Blizzard's lack of using real testers would not have got them off the ground all those years ago because of all the issues over the past few years. This isn't just me complaining either- it's an ongoing JOKE about there being many more problems for every patch to fix small things and it's coming from players who have been around since BC & Vanilla, not the "kiddies".

Had this issue also, I went into my update folder and deleted ALL the MPQ files, started up fine. When I did just 16357 it would get stuck during the update and when i would reopen I would get the same error.

By reopening the launch the game will begin to repatch itself by downloading that file again.As some mentioned you may have to delete the file itself if you get the corrupt error message which will also contain the path to get to the file- usually programfilesx86/worldofwarcraft/updates/winfinal.mpqUsing the repair tool might fix this for you without having to do anything though. The repair tool can be found under help on the launcher.

Can you tell me the exact name of it and where it's located? I had the same problem, ty.

The name of it and path of where to find it is in the error message lol

Deleted it a bunch of times, it's working now. What's really weird is it seemed the file never fully deleted. >.> Went from 0% to 90% right away with 2.3mb left, then done. Was saying 263kb left at 95% or 99.9%.

Might of still had launcher.exe and agent.exe open. Make sure those processes are not open in the task manager before deleting.

The repair tool under "Help" fixed this right up for me as well. I definitely recommend you try Blizzard's in-game option before you start deleting things.

That's the Help menu in the menu bar when you have the Launcher open everyone.